Fiber optic systems comprised of optical fibers and electro-optic components are widely used in a variety of applications, such as telecommunication of information and the like. Optical fibers have a small diameter core of a transparent material and a cladding of a polymeric material formed about the outer surface of the core. However, optical fibers are relatively weak and are especially subject to breakage when strain is applied to the fibers. Also, if strain is applied to the optical fibers of a fiber optic system, the fibers can be forced out of alignment with a electro-optic component causing the system to become inoperative. Thus, the optical fibers are conventionally encased in a fiber optic cable to protect them from damage and to prevent misalignment. The most widely used type of fiber optic cables have an optical fiber positioned in the center of the cable, a plurality of reinforcement strands positioned circumferentially about the optical fiber and aligned with the length of the optical fiber to relieve strain on the optical fiber, and an outer jacket disposed over and about the reinforcement strands.
The electro-optic components employed with fiber optic systems include a wide variety of different types of devices, such as light emmitters, light detectors and signal repeaters. Many of the electro-optic components are highly sensitive to environmental contaminants and are highly susceptible to physical damage. To prevent damage to the components they are packaged in sealed protective housings. The component housings are made in various configurations to accommodate the different types of devices and include an opening for passage of an optical fiber into the interior of the housing for alignment with the encased component.
When assembling a typical fiber optic system, a terminal end of an optical fiber is precisely aligned with an electro-optic component in a component housing and secured in position. The component housing is then preferably hermetically sealed and the remaining portion of the fiber optic cable, that is, the reinforcement fibers and the jacket, are trimmed and secured to the component housing, typically with an optical fiber coupling or a length of shrink-fit tubing.
The termination of the fiber optic cable with the component housing presents serious problems from both a production standpoint and a performance standpoint. Certain of the methods heretofore suggested require a relatively complex series of steps and a skilled operator in order to make a satisfactory termination of the fiber optic cable. Certain other suggested methods employ fittings similar to those used in optical fiber couplings which result in the termination being excessively large. The most serious problem encountered with the suggested methods is that the terminations produced by the suggested methods do not provide adequate strain relief to prevent movement and misalignment of the optical fiber within the component housing when the fiber optic cable is subjected to strain.
What would be highly desirable would be a method for forming a termination of a fiber optic cable with a component housing, which termination is simple to form, compact and provides strain relief for the optical fiber.